Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
One of the more important components in present-day wireless communication equipment is the radio frequency (RF) switch. Integrated circuit (IC) designs typically include a transmitter section, a receiver section, and an RF switch on the same IC (sometimes referred to as an “on-chip” design). The purpose of an RF switch is to connect an external antenna between the transmitter section and the receiver section of the IC. Accordingly, such switches are commonly referred to as transmit/receive (TR) switches.
Challenges exist in the design of TR switches. One challenge relates to the unavoidable use of inductors in the design, primarily to provide impedance matching between the antenna and the input circuitry in the receiver section. Conventional designs offer one-pin TR switches which incorporate one or more inductors in their design. Such “on-chip” inductors tend to be large (they take up a lot of chip space), and electrically speaking, they tend to be “lossy’ which can lead to an increase in the noise figure in the receive path and to insertion loss in the transmit path. The design criteria for minimizing insertion loss and non-linear effects in transmit mode are sometimes at odds with the design criteria for optimizing impedance matching between the antenna and the receiver section and minimizing the noise figure of the receiver section.